The present invention relates to a vehicle liftgate and, more particularly, to a control system therefor.
Vans, station wagons, pick-ups, and sport-utility vehicles (SUVs) typically have rear doors, generically called tailgates, which provide access to the vehicle's rear cargo area through a rear opening. In some vehicles, pairs of doors are vertically hinged at the sides of the rear opening to open horizontally. In others, pairs of doors are horizontally hinged at the top and bottom of the rear opening to open vertically up and down like a clamshell. In yet other vehicles, a single door or liftgate is horizontally hinged at the top of the opening to open upwardly.
Liftgates are usually fitted with cylindrical devices filled with pressurized gas at the sides to provide a spring assist when the door is raised. These cylindrical devices are commonly referred to as gas springs, gas struts, gas props, gas stays, or stay dampers. Manual effort may be required to both raise and lower the liftgate even though the gas springs aid lifting and gravity aids lowering. Manual operation necessitates operator presence at the liftgate for operation, which may be undesirable during inclement weather and may be difficult for some people.
Many vehicles are currently incorporating powered actuators to automatically open and close the liftgates. Although effective, the powered actuators operate generally in accordance with the manual systems. As with manual systems, the powered actuators move the liftgate between a fully open and a fully closed position.
Accordingly, it is desirable to provide a control system that selectively positions a vehicle liftgate.